Dissatisfied with a reported $61-million bid, Lucara Diamond TSX:LUC declined to sell its 1,109-carat Lesedi La Rona stone. The company had hoped Sotheby’s June 29 London event would pull in $70 million or more.

The stone’s currently the largest gem-quality diamond in captivity and history’s second largest after the 3,106.75-carat Cullinan diamond. Found in 1905, Cullinan was cut and polished into nine gems for the Crown jewels and royal sceptre. Lucara took the unusual step of delegating the Lesedi La Rona sales job to an auctioneer, not standard procedure for rough. But a heavy promotional campaign failed to find a sufficiently astronomical price.

Despite its record size, as well as exceptional quality and transparency, the Lesedi La Rona drew disappointing bids.(Photo: Donald Bowers/Getty Images for Sotheby’s)

Yet the miner’s expectations might have been understandable. In May Lucarasold its 812.77-carat Constellation for $63.11 million, or $77,649 per carat, “the highest price ever achieved for a rough diamond,” the company stated. Lucara kept a 10% interest in Constellation’s sale after being cut and polished.

In April, however, Sotheby’s rejected a top bid of $22 million for the 9.54-carat Shirley Temple Blue diamond, having hoped for $25 million to $35 million.

Lucara’s recent record finds came from its Karowe mine in Botswana, aided by an improved recovery circuit. The two Josephines came from South Africa’s Cullinan mine, now operated by Petra Diamonds. That company’s most recent large find weighs in at 121.26 carats. It’s currently on tender.

Earlier this month ALROSA announced one of Russia’s biggest finds, a 241.21-carat rough that followed the previous month’s 207.29-carat stone, each from a different pipe at Yakutia in Siberia.